use std::{collections::BTreeSet, convert::Infallible, io, path::Path, sync::atomic::Ordering, time::Instant}; use anyhow::{anyhow, bail}; use gix::{    actor,    bstr::{BStr, ByteSlice},    interrupt,    prelude::*,    progress, Progress,}; /// Additional configuration for the hours estimation functionality.pub struct Context<W> {    /// Ignore github bots which match the `[bot]` search string.    pub ignore_bots: bool,    /// Show personally identifiable information before the summary. Includes names and email addresses.    pub show_pii: bool,    /// Collect how many files have been added, removed and modified (without rename tracking).    pub file_stats: bool,    /// Collect how many lines in files have been added, removed and modified (without rename tracking).    pub line_stats: bool,    /// The amount of threads to use. If unset, use all cores, if 0 use al physical cores.    pub threads: Option<usize>,    /// Omit unifying identities by name and email which can lead to the same author appear multiple times    /// due to using different names or email addresses.    pub omit_unify_identities: bool,    /// Where to write our output to    pub out: W,} /// Estimate the hours it takes to produce the content of the repository in `_working_dir_`, with `_refname_` for/// the start of the commit graph traversal.////// * _working_dir_ - The directory containing a '.git/' folder./// * _refname_ - The name of the ref like 'main' or 'master' at which to start iterating the commit graph./// * _progress_ - A way to provide progress and performance informationpub fn estimate<W, P>(    working_dir: &Path,    rev_spec: &BStr,    mut progress: P,    Context {        show_pii,        ignore_bots,        file_stats,        line_stats,        omit_unify_identities,        threads,        mut out,    }: Context<W>,) -> anyhow::Result<()>where    W: io::Write,    P: Progress,{    let repo = gix::discover(working_dir)?;    let commit_id = repo.rev_parse_single(rev_spec)?.detach();    let mut string_heap = BTreeSet::<&'static [u8]>::new();    let needs_stats = file_stats || line_stats;    let threads = {        let t = threads.unwrap_or_else(num_cpus::get);        (t == 0).then(num_cpus::get_physical).unwrap_or(t)    };     let (commit_authors, stats, is_shallow, skipped_merge_commits) = {        let stat_progress = needs_stats.then(|| progress.add_child("extract stats")).map(|mut p| {            p.init(None, progress::count("commits"));            p        });        let stat_counter = stat_progress.as_ref().and_then(|p| p.counter());         let change_progress = needs_stats.then(|| progress.add_child("find changes")).map(|mut p| {            p.init(None, progress::count("modified files"));            p        });        let change_counter = change_progress.as_ref().and_then(|p| p.counter());         let lines_progress = line_stats.then(|| progress.add_child("find changes")).map(|mut p| {            p.init(None, progress::count("diff lines"));            p        });        let lines_counter = lines_progress.as_ref().and_then(|p| p.counter());         let mut progress = progress.add_child("traverse commit graph");        progress.init(None, progress::count("commits"));         std::thread::scope(|scope| -> anyhow::Result<_> {            let start = Instant::now();            let (tx, rx) = std::sync::mpsc::channel::<(u32, Vec<u8>)>();            let mailmap = repo.open_mailmap();             let commit_thread = scope.spawn(move || -> anyhow::Result<Vec<_>> {                let mut out = Vec::new();                for (commit_idx, commit_data) in rx {                    if let Ok(author) = gix::objs::CommitRefIter::from_bytes(&commit_data)                        .author()                        .map(|author| mailmap.resolve_cow(author.trim()))                    {                        let mut string_ref = |s: &[u8]| -> &'static BStr {                            match string_heap.get(s) {                                Some(n) => n.as_bstr(),                                None => {                                    let sv: Vec<u8> = s.to_owned();                                    string_heap.insert(Box::leak(sv.into_boxed_slice()));                                    (*string_heap.get(s).expect("present")).as_ref()                                }                            }                        };                        let name = string_ref(author.name.as_ref());                        let email = string_ref(author.email.as_ref());                         out.push((                            commit_idx,                            actor::SignatureRef {                                name,                                email,                                time: author.time,                            },                        ));                    }                }                out.shrink_to_fit();                out.sort_by(|a, b| {                    a.1.email.cmp(b.1.email).then(                        a.1.time                            .seconds_since_unix_epoch                            .cmp(&b.1.time.seconds_since_unix_epoch)                            .reverse(),                    )                });                Ok(out)            });             let (tx_tree_id, stat_threads) = needs_stats                .then(|| {                    let (tx, rx) =                        crossbeam_channel::unbounded::<Vec<(u32, Option<gix::hash::ObjectId>, gix::hash::ObjectId)>>();                    let stat_workers = (0..threads)                        .map(|_| {                            scope.spawn({                                let commit_counter = stat_counter.clone();                                let change_counter = change_counter.clone();                                let lines_counter = lines_counter.clone();                                let mut repo = repo.clone();                                repo.object_cache_size_if_unset((850 * 1024 * 1024) / threads);                                let rx = rx.clone();                                move || -> Result<_, anyhow::Error> {                                    let mut out = Vec::new();                                    for chunk in rx {                                        for (commit_idx, parent_commit, commit) in chunk {                                            if let Some(c) = commit_counter.as_ref() {                                                c.fetch_add(1, Ordering::SeqCst);                                            }                                            if gix::interrupt::is_triggered() {                                                return Ok(out);                                            }                                            let mut files = FileStats::default();                                            let mut lines = LineStats::default();                                            let from = match parent_commit {                                                Some(id) => {                                                    match repo.find_object(id).ok().and_then(|c| c.peel_to_tree().ok())                                                    {                                                        Some(tree) => tree,                                                        None => continue,                                                    }                                                }                                                None => repo.empty_tree(),                                            };                                            let to =                                                match repo.find_object(commit).ok().and_then(|c| c.peel_to_tree().ok())                                                {                                                    Some(c) => c,                                                    None => continue,                                                };                                            from.changes()?                                                .track_filename()                                                .track_renames(None)                                                .for_each_to_obtain_tree(&to, |change| {                                                    use gix::object::tree::diff::change::Event::*;                                                    if let Some(c) = change_counter.as_ref() {                                                        c.fetch_add(1, Ordering::SeqCst);                                                    }                                                    match change.event {                                                        Copy { .. } | Rename { .. } => {                                                            unreachable!("we turned that off")                                                        }                                                        Addition { entry_mode, id } => {                                                            if entry_mode.is_no_tree() {                                                                files.added += 1;                                                                add_lines(                                                                    line_stats,                                                                    lines_counter.as_deref(),                                                                    &mut lines,                                                                    id,                                                                );                                                            }                                                        }                                                        Deletion { entry_mode, id } => {                                                            if entry_mode.is_no_tree() {                                                                files.removed += 1;                                                                remove_lines(                                                                    line_stats,                                                                    lines_counter.as_deref(),                                                                    &mut lines,                                                                    id,                                                                );                                                            }                                                        }                                                        Modification {                                                            entry_mode,                                                            previous_entry_mode,                                                            id,                                                            previous_id,                                                        } => {                                                            match (previous_entry_mode.is_blob(), entry_mode.is_blob())                                                            {                                                                (false, false) => {}                                                                (false, true) => {                                                                    files.added += 1;                                                                    add_lines(                                                                        line_stats,                                                                        lines_counter.as_deref(),                                                                        &mut lines,                                                                        id,                                                                    );                                                                }                                                                (true, false) => {                                                                    files.removed += 1;                                                                    remove_lines(                                                                        line_stats,                                                                        lines_counter.as_deref(),                                                                        &mut lines,                                                                        previous_id,                                                                    );                                                                }                                                                (true, true) => {                                                                    files.modified += 1;                                                                    if line_stats {                                                                        let is_text_file = mime_guess::from_path(                                                                            gix::path::from_bstr(change.location)                                                                                .as_ref(),                                                                        )                                                                        .first_or_text_plain()                                                                        .type_()                                                                            == mime_guess::mime::TEXT;                                                                        if let Some(Ok(diff)) = is_text_file                                                                            .then(|| change.event.diff())                                                                            .flatten()                                                                        {                                                                            let mut nl = 0;                                                                            let counts = diff.line_counts();                                                                            nl += counts.insertions as usize                                                                                + counts.removals as usize;                                                                            lines.added += counts.insertions as usize;                                                                            lines.removed += counts.removals as usize;                                                                            if let Some(c) = lines_counter.as_ref() {                                                                                c.fetch_add(nl, Ordering::SeqCst);                                                                            }                                                                        }                                                                    }                                                                }                                                            }                                                        }                                                    }                                                    Ok::<_, Infallible>(Default::default())                                                })?;                                            out.push((commit_idx, files, lines));                                        }                                    }                                    Ok(out)                                }                            })                        })                        .collect::<Vec<_>>();                    (Some(tx), stat_workers)                })                .unwrap_or_default();             let mut commit_idx = 0_u32;            let mut skipped_merge_commits = 0;            const CHUNK_SIZE: usize = 50;            let mut chunk = Vec::with_capacity(CHUNK_SIZE);            let commit_iter = interrupt::Iter::new(                commit_id.ancestors(|oid, buf| {                    progress.inc();                    repo.objects.find(oid, buf).map(|obj| {                        tx.send((commit_idx, obj.data.to_owned())).ok();                        if let Some((tx_tree, first_parent, commit)) = tx_tree_id.as_ref().and_then(|tx| {                            let mut parents = gix::objs::CommitRefIter::from_bytes(obj.data).parent_ids();                            let res = parents                                .next()                                .map(|first_parent| (tx, Some(first_parent), oid.to_owned()));                            match parents.next() {                                Some(_) => {                                    skipped_merge_commits += 1;                                    None                                }                                None => res,                            }                        }) {                            if chunk.len() == CHUNK_SIZE {                                tx_tree                                    .send(std::mem::replace(&mut chunk, Vec::with_capacity(CHUNK_SIZE)))                                    .ok();                            } else {                                chunk.push((commit_idx, first_parent, commit))                            }                        }                        commit_idx = commit_idx.checked_add(1).expect("less then 4 billion commits");                        gix::objs::CommitRefIter::from_bytes(obj.data)                    })                }),                || anyhow!("Cancelled by user"),            );            let mut is_shallow = false;            for c in commit_iter {                match c? {                    Ok(c) => c,                    Err(gix::traverse::commit::ancestors::Error::FindExisting { .. }) => {                        is_shallow = true;                        break;                    }                    Err(err) => return Err(err.into()),                };            }            if let Some(tx) = tx_tree_id {                tx.send(chunk).ok();            }            drop(tx);            progress.show_throughput(start);            drop(progress);             let stats_by_commit_idx = match stat_progress {                Some(mut progress) => {                    progress.set_max(Some(commit_idx as usize - skipped_merge_commits));                    let mut stats = Vec::new();                    for handle in stat_threads {                        stats.extend(handle.join().expect("no panic")?);                        if gix::interrupt::is_triggered() {                            bail!("Cancelled by user");                        }                    }                    stats.sort_by_key(|t| t.0);                    progress.show_throughput(start);                    stats                }                None => Vec::new(),            };            if let Some(mut progress) = change_progress {                progress.show_throughput(start);            }            if let Some(mut progress) = lines_progress {                progress.show_throughput(start);            }             Ok((                commit_thread.join().expect("no panic")?,                stats_by_commit_idx,                is_shallow,                skipped_merge_commits,            ))        })?    };     if commit_authors.is_empty() {        bail!("No commits to process");    }     let start = Instant::now();    let mut current_email = &commit_authors[0].1.email;    let mut slice_start = 0;    let mut results_by_hours = Vec::new();    let mut ignored_bot_commits = 0_u32;    for (idx, (_, elm)) in commit_authors.iter().enumerate() {        if elm.email != *current_email {            let estimate = estimate_hours(&commit_authors[slice_start..idx], &stats);            slice_start = idx;            current_email = &elm.email;            if ignore_bots && estimate.name.contains_str(b"[bot]") {                ignored_bot_commits += estimate.num_commits;                continue;            }            results_by_hours.push(estimate);        }    }    if let Some(commits) = commit_authors.get(slice_start..) {        results_by_hours.push(estimate_hours(commits, &stats));    }     let num_authors = results_by_hours.len();    let mut results_by_hours = if !omit_unify_identities {        deduplicate_identities(&results_by_hours)    } else {        results_by_hours            .iter()            .fold(Vec::with_capacity(results_by_hours.len()), |mut acc, e| {                acc.push(e.into());                acc            })    };    let elapsed = start.elapsed();    progress.done(format!(        "Extracted and organized data from {} commits in {:?} ({:0.0} commits/s)",        commit_authors.len(),        elapsed,        commit_authors.len() as f32 / elapsed.as_secs_f32()    ));     let num_unique_authors = results_by_hours.len();    let (total_hours, total_commits, total_files, total_lines) = results_by_hours        .iter()        .map(|e| (e.hours, e.num_commits, e.files, e.lines))        .reduce(|a, b| (a.0 + b.0, a.1 + b.1, a.2.clone().added(&b.2), a.3.clone().added(&b.3)))        .expect("at least one commit at this point");    if show_pii {        results_by_hours.sort_by(|a, b| a.hours.partial_cmp(&b.hours).unwrap_or(std::cmp::Ordering::Equal));        for entry in results_by_hours.iter() {            entry.write_to(                total_hours,                file_stats.then_some(total_files),                line_stats.then_some(total_lines),                &mut out,            )?;            writeln!(out)?;        }    }    writeln!(        out,        "total hours: {:.02}\ntotal 8h days: {:.02}\ntotal commits = {}{}\ntotal authors: {}",        total_hours,        total_hours / HOURS_PER_WORKDAY,        total_commits,        is_shallow.then_some(" (shallow)").unwrap_or_default(),        num_authors    )?;    if file_stats {        writeln!(            out,            "total files added/removed/modified/remaining: {}/{}/{}/{}",            total_files.added,            total_files.removed,            total_files.modified,            total_files.added - total_files.removed        )?;    }    if line_stats {        writeln!(            out,            "total lines added/removed/remaining: {}/{}/{}",            total_lines.added,            total_lines.removed,            total_lines.added - total_lines.removed        )?;    }    if !omit_unify_identities {        writeln!(            out,            "total unique authors: {} ({:.02}% duplication)",            num_unique_authors,            (1.0 - (num_unique_authors as f32 / num_authors as f32)) * 100.0        )?;    }    if ignored_bot_commits != 0 {        writeln!(out, "commits by bots: {}", ignored_bot_commits)?;    }    if needs_stats && skipped_merge_commits != 0 {        writeln!(out, "stats omitted for {} merge commits", skipped_merge_commits)?;    }    assert_eq!(        total_commits,        commit_authors.len() as u32 - ignored_bot_commits,        "need to get all commits"    );    Ok(())} mod core;use self::core::{deduplicate_identities, estimate_hours, HOURS_PER_WORKDAY}; mod util;use util::{add_lines, remove_lines, FileStats, LineStats, WorkByEmail, WorkByPerson};